If you know you have to be at work every weekday morning at 8 o’clock and are off at 5 o’clock, it is not difficult to remember your schedule. Not everyone is lucky enough to have a permanent schedule.

Shifts is a calendar app specifically designed for people who work different hours all of the time. Whether you are on-call every other weekend, work the night shift twice per month, or have two jobs to juggle, this app makes keeping track of your schedule a bit easier.

Users start by creating shifts. Enter the shift name (like, busboy or on-call). Then choose a start and end time. If you get a varying rate of pay, you can also include your hourly rate. Select an icon to identify the type of shift easily on the monthly view.

After you’ve added all of your shifts, you can populate your calendar with them. Go back to the monthly view and tap the plus (+) icon at the bottom of the screen. Then, select the shift you wish to add. Tap the date on the calendar you want to import that shift into. You can add a maximum of two shifts per day.

Then, move on to the next shift.

You can also set up customized shift rotations. So if you know you are on call every other week, set up a rotation that will automatically populate your year’s schedule.

You can also add notes to daily shifts. For example, if you are working at the candy counter at a movie theater, you can include in the note whether you are working lead or back up.

You can overlay your personal calendar into Shifts so you can see at a glance everything you’ve got going on this month.

It is easy to share your Shifts calendar with others. Tap the Share icon to send a copy of the month via email, SMS, Facebook, and more.

Shifts can also be added to the Today view of your Notification Center so you can view your upcoming shifts right from your lock screen. Set up shift reminders to get an alert before your next shift. No more excuses for being late to work.

Shifts is on sale for $1.99 for a limited time. After the sale, it will increase to $4.99. If you work irregular hours, this app might just save you from missing your shift. Download it in the App Store today.